# Sampling distribution of the sample means central

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Sampling distribution of the samplemeans.Central Limit TheoryThe mean of ALL the sample means equal to population mean: µx= µThe standard deviation of the sample means is σx¯=σn√σx¯=σn
Problem 1The final exam mark for a class is normally distributed with a mean of 63 and standard deviation of 15.A student got 60 for his final exam.What is the Z-Score for his final exam mark?
Z-Score for his final exam mark?
Problem 2The final exam mark for a class is normally distributed with a mean of 63 and standard deviation of 15.What is the probability that a randomly selected student’s mark is greater than 70?
What is the probability that a randomly selected student’s mark is greater than 70?Using the CASIO calculator: Select STAT F5(DIST; F1 (NORM ; F2 (Ncd); F2 (Var);
Problem 3The weight of adults is normally distributed with mean μ = 170 lb and standard deviation σ = 25lbs.Suppose a random sample of size n = 6adults is selected.
What is the probability that the sample mean is between 150 lb and 190 lb?
Suppose a random sample of size n = 6adults is selected.What is the probability that the sample mean is between 150 lb and 190 lb?Using the CASIO calculator: Select STAT F5(DIST; F1 (NORM); F2 (Ncd); F2 (Var);
Module 2 – Confidence Interval Estimation and Sample SizeKey Terms and ConceptsHere is a list of key terms and concepts presented in this module, assigned readings, and resources. It isimportant that you understand what they represent within the context of this course. After studying the learning materials provided in this module, if you need clarification on any of theseterms, please ask your instructor for help. Confidence Interval:an interval that contains the population mean or the population proportion.z Value:a standard normal value where the mean is zero and standard deviation is 1. It is also knownas zcritical value or z-scores.
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